OAKLAND, Calif. (AP) -- Riot-clad law enforcement officers cleared out a weeks-old anti-Wall Street encampment in Oakland just before dawn Monday, arresting dozens of Occupy demonstrators and clearing out tents from a downtown plaza after issuing several warnings over the weekend. Protesters appeared to put up little resistance and officers could be seen leading some handcuffed demonstrators away. Warnings from authorities had been similar to those issued before officers used tear gas and bean bag projectiles to clear the encampment on Oct. 25. Police and sheriff's deputies blocked off surrounding streets before Monday's raid. Afterward, some demonstrators gathered near the barricades and vowed to return. "I don't see how they're going to disperse us," said Ohad Meyer, 30, of Oakland. "There are thousands of people who are going to come back." The action came a day after police drove hundreds of anti-Wall Street demonstrators from weeks-old encampments in Portland, arresting more than 50 people. Oakland officials stepped up calls for an end to their city's encampment after a man was shot and killed Thursday near the plaza. Police issued a fourth cease and desist order Sunday night telling demonstrators they couldn't camp there. Mayor Jean Quan had allowed protesters to reclaim the disbanded site after facing criticism following the Oct. 25 raid. The camp grew substantially afterward, although city officials said on Sunday the number of tents has dropped by about 30 to 150 since Nov. 8. Officials across the country have been urging an end to similar gatherings in the wake of three deaths in different cities, including two deaths by gunfire. Demands for Oakland protesters to pack up increased after a man was shot and killed Thursday near the encampment site. Protesters had said that there was no connection between the shooting and the camp. But police Sunday night identified the slain man as 25-year-old Kayode Ola Foster of Oakland, saying his family confirmed he had been staying at the plaza. Police officer Johnna Watson said witnesses have told police that one of two suspects in the shooting had also been a frequent resident at the plaza. The suspects are being sought and their names haven't been released. Investigators suspect that the shooting resulted from a fight between two groups of men. In the hours after the midnight Saturday eviction deadline in Portland, the anti-Wall Street protesters and their supporters had flooded the park area. At one point, the crowd swelled to thousands. As dawn arrived, riot police had retreated and most of the crowds had gone home, but protesters who have been at the two parks since Oct. 6 were still there, prompting one organizer to declare the night a victory for the movement. "We stood up to state power," Jim Oliver told The Associated Press. It didn't last. Police moved in later. An officer on a loudspeaker warned that anyone who resisted risked arrest and "may also be subject to chemical agents and impact weapons." Demonstrators chanted "we are a peaceful protest." "We were talking about what we were going to do and then they just started hitting people. Seems like a waste of resources to me," protester Mike Swain, 27, told the AP. One man was taken away on a stretcher; he was alert and talking to paramedics, and raised a peace sign to fellow protesters, who responded with cheers. City officials erected temporary chain-link fences with barbed wire at the top around three adjacent downtown parks, choking off access for demonstrators as parks officials cleaned up. Portland Mayor Sam Adams Sunday defended his order to clear the park, saying it is his job to enforce the law and keep the peace. "This is not a game," Adams said. Officials said that one officer suffered minor injuries. Police had prepared for a possible clash, warning that dozens of anarchists may be planning a confrontation with authorities. In other cities over the weekend: - In Salt Lake City, police arrested 19 people Saturday when protesters refused to leave a park a day after a man as found dead inside his tent at the encampment. - In Albany, N.Y., police arrested 24 Occupy Albany protesters after they defied an 11 p.m. curfew in a state-owned park. - In Denver, authorities arrested four people as they forced protesters to leave a downtown encampment. - In San Francisco, police said two demonstrators attacked two police officers in separate incidents during a march, leaving them with minor injuries. The assailants couldn't be located.